(a) Field of the Invention
The present invention relates to a display device and a manufacturing method of the same, and more particularly, to a display device, which is capable of reducing pixel defects by alternately forming polymer organic layers and low molecular weight organic layers, and a manufacturing method of the same.
(b) Description of the Related Art
Among flat panel displays, organic light emitting diodes (“OLEDs”) have been recently spotlighted because of their low voltage driving, light weight, thinness, wide viewing angle and high speed response, for example. An OLED is categorized as either a passive matrix type and an active matrix type. The passive matrix type OLED has disadvantages including rapid increase of power consumption with larger display areas and higher resolution, although it has a relatively simple manufacturing process. For this reason, the passive matrix type OLED is mainly applied to a small-sized display devices. In contrast, the active matrix type OLED has a merit of a large screen size and a high resolution although it has a relatively complicated manufacturing process.
The active matrix type OLED controls light emission of a light emitting layer for each pixel region to which a transistor is connected. A pixel electrode is provided in each pixel region and each pixel electrode is electrically isolated from adjacent pixel electrodes for independent driving thereof. Organic layers including a light emitting layer are sequentially formed on the pixel electrodes. A common electrode is formed on the light emitting layer.
The organic layers in the OLED are formed by a wet method or a dry method. The wet method is used to form a polymer organic layer, including an inkjet method, a spin coating method, a spray coating method, a roll-to-roll method, a nozzle coating method, etc. The dry method is used to form a low molecular weight organic layer, primarily including an evaporation method.
However, although the wet method is adapted to fabricating a large OLED and has a merit of less material consumption, it also has a problem of pixel defects since an organic layer does not entirely cover a pixel electrode.